To overlook a growing problem for immediate gain just breeds trouble in the long run. Tarun Gogoi, the chief minister of Assam’s Congress government, might have reflected on this, had he and his party not participated in perpetuating Assam’s inherited problem of illegal migrants from Bangladesh. Violent movements against “foreigners” in the state are not new; demographic changes caused by illegal migrants have bred aggression among the people and opportunities for politicians. They form a vote bank politicians are unwilling to sacrifice. This time the spur to another bout of ousting “foreigners” has come from the accusation of Arunachal Pradesh and Nagaland that Assam protects illegal migrants, and the remarks of a judge of the Guwahati high court that entrants from Bangladesh have become “king makers”. Identifying offenders has never been easy, since anyone occupying land for more than three years can manage to get the papers to show he is a resident. Such efforts inevitably begin to look like vendettas against specific groups of people — in some cases speakers of Bengali or Hindi, and in others those belonging to the minority community.

The last is the greatest danger now. The All Assam Students’ Union is being accused of rounding up “suspects” who are Indians from the minority community. Predictably, conflict is brewing with students belonging to the community. Its leaders have strongly urged care in the identification of offenders, while the Congress is worried about the minority vote. Mr Gogoi has asked the Union home minister for better fences and stricter guard on the rivers bordering the state. Having admitted to a lack of data about the number of illegal migrants, he also wishes to update of the national register of citizens. Additionally, the Assam government might look into possible changes in the Assam Land Revenue Regulation Act, to prevent illegal migrants from claiming citizenship after three years. Perhaps Mr Gogoi is feeling pressured, perhaps he would like to appear serious. But a politician knows best how a register can be manipulated or how migrants without papers are allowed to acquire them so that they can lay claim to land. It is a question of political will in the service of a right and just purpose, not of stricter laws, better-kept registers, better-trained border forces or mended fences.